High tension cable barrier for roadways

ABSTRACT

A barrier fence for use along the side of a roadway to contain a vehicle that travels off of the roadway into the barrier fence. The fence includes horizontal fence members which are typically cables supported by a plurality of posts supported vertically by the ground. The horizontal fence members are held to the posts with hooks that extend from slots defined by the posts. The horizontal fence members are placed in tension in normal use. Each post has a wide, flat, contact surface across the front of the post for the horizontal fence member to contact on either side of the slot that receives the hook that holds the horizontal fence member. The fence provides posts with flat front surfaces substantially wider than the width of the slot to increase the length of engagement between the post surface and the horizontal fence member.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Patent Application Ser. No. 62/308,780 filed 15 Mar. 2016; the disclosures of which are incorporated herein by reference.

BACKGROUND OF THE DISCLOSURE

1. Field of the Invention

The disclosure relates to roadway safety barriers and, more particularly, to high tension cable barriers. Specifically, the disclosure relates to high tension cable barriers wherein the cables are connected to posts by hooks that hold the cables against an outer surface of the post.

2. Background Information

Guardrail systems are widely used along heavily traveled roadways to enhance the safety of the roadway and adjacent roadside. One such system includes a guardrail beam, such as a “W-beam” (named after its characteristic shape), and corresponding support posts. Other systems may utilize cables and corresponding support posts. These systems are used to stop or redirect vehicles which have left the designated roadway.

One guard fence that uses cables supported by posts is disclosed in US Patent Application Publication 2002/0014620. This guard fence includes a plurality of spaced, substantially vertical posts that support a plurality of cables with hooks. The hooks have ends that project in opposite directions such that the hooks can be fit into slots defined by the post. The hooks hold the cable against the exterior surface of the post. The posts with the cables disposed on the exterior surface have rounded cross sections and thus limit the contact area between the post and the cable.

SUMMARY OF THE DISCLOSURE

The disclosure provides a barrier fence for use along the side of a roadway to contain a vehicle that travels off of the roadway into the barrier fence. The fence includes horizontal fence members which are typically cables supported by a plurality of posts supported vertically by the ground. The horizontal fence members are held to the posts with hooks that extend from slots defined by the posts. The horizontal fence members are placed in tension in normal use. The fence is configured for use with ground that slopes down and away from the roadway to define a slope. Such sloped conditions provide less support for a fence post because there is less support on the backside of the post.

The disclosure provides a barrier fence that provides sufficient post strength and fence member retention to retain a vehicle that leave the roadway and collides with the barrier under defined MASH16 standard test conditions. The post components of the fence are located based on the inclination of the slope and a substantial length of the post is disposed underground to provide support for the barrier. In the exemplary configuration, at least 1198 millimeters of post length is disposed underground as measured on the up-slope wall of the post.

One feature of the disclosure is a wide, flat, contact surface across the front of the post for the horizontal fence member to contact on either side of the slot that receives the hook that holds the horizontal fence member. The fence provides posts with flat front surfaces substantially wider than the width of the slot to increase the length of engagement between the post surface and the horizontal fence member. This moves the corner of the post farther away from the slot than in round or oval posts.

The disclosure provides a fence having long posts with each having a hollow rectangular cross section that provides a wide front, roadway-facing surface which is to be engaged by the horizontal fence member when the member is held by the hook. The post can define an opening disposed along the entire length of the back wall.

In an exemplary configuration, the overall length of the post is 2256 millimeters and, when in use, about 1298 millimeters is disposed below the roadway surface with about 1198 millimeters being disposed below the surface of the ground to provide 958 millimeters of post length above the roadway surface to support the horizontal fencing members. Three horizontal fence members can be vertically spaced 185 millimeters with the lowest being about 530 millimeters above the roadway surface. In this configuration, a fourth horizontal fencing member can be added 92.5 millimeters below the top one to provide a fence that fulfils a four-cable requirement. The top horizontal fence members of both of these configurations are positioned about 900 millimeters above the roadway surface. This post configuration and horizontal fence member placement allows the top horizontal fence member to be disposed at a higher position above the roadway surface which is useful for newer SUVs and trucks which have panels and bumpers higher off the ground.

The disclosure provides a barrier fence having a plurality of horizontal fence members such as cables supported from a plurality of hooks that are carried by slots defined by a plurality of posts. The post configuration provides the wide flat front face having a long contact surface about six to eight times as long as the width of the hook slot. The corners are rounded and terminate at about the wall thickness. The curved surface of the corners are not included in the measurement of the cable contact surface. When a vehicle impacts the horizontal fence member or the post and the horizontal fence member and the horizontal fence member is driven back against the post, the long contact surface is believed to help the hook remain seated. The horizontal fence member has a larger surface to rest against and the larger area creates higher friction, which helps the horizontal fence member to stay in place longer. The overall combination of the stronger post, the larger flat contact surface, and the resulting higher friction enables this combination to perform to retain the vehicle. The overall depth of the post is over 11 times the width of the slot. For example, the post can be 83 millimeters deep and 64 millimeters wide with a wall thickness of 4 millimeters such that the front cable contact surface is 56 millimeters less the horizontal width of the hook slot which is 7 millimeters. This leaves a surface of 49 millimeters which is seven times the horizontal slot width. The slots are not necessarily centered with respect to the front surface of the post.

The disclosure provides a hook configuration that functions in cooperation with the post configuration to provide a strong connection between the cable and the post.

The disclosure also provides a hook for securing a portion of a cable to a post wherein the hook has a 6 millimeters diameter body with oppositely-projecting ends that extend 12.5 millimeters from either side of the main body of the hook. These ends can engage the inner surface of the front wall of the wall along their lengths.

The disclosure also provides an optional configuration wherein the slot defined by the post is closed with a plug after the hook is installed. Each plug substantially fills the upper portion of a slot. These plugs help maintain the position of the hook with respect to the post when the cables are moved in response to weather, ground changes, an impact with the cables from mowers or other maintenance vehicles, or other events that cause the cables to move. The plugs can be provided as deformable, resilient polymer members that can be snap fit into the slots with locking ribs holding the position of the plugs with respect to the posts.

The disclosure provides a simple and reliable arrangement for anchoring the horizontal fence members of the barrier to the vertical posts of the fence. The fence provides a plurality of posts having roadway-facing surfaces that define flat, long contact surfaces that are in contact with the horizontal fence members along a horizontal engagement portion. An exemplary configuration of the post has a substantially rectangular cross section with a flat front, roadway-facing surface that defines the slots that receive the hooks. Another exemplary configuration of the post has at least a flat front, roadway-facing surface, with rounded corners that connect the flat front surface to the sidewalls. Another configuration of the post has an open back wall disposed opposite the flat front surface.

The posts are substantially vertically anchored. The fence also comprises substantially horizontal, longitudinal fence members that are attached to the posts and are arranged at mutually spaced apart distances from each other in a vertical direction. The horizontal fence members are anchored to the posts by retaining members that are adapted to retain the horizontal fence members during forces caused by collision in a longitudinal direction of the fence members and to release the horizontal fence members when acted upon by forces generated by collisions against a post to which the horizontal fence members are anchored.

The preceding non-limiting aspects, as well as others, are more particularly described below. A more complete understanding of the processes and equipment can be obtained by reference to the accompanying drawings, which are not intended to indicate relative size and dimensions of the assemblies or components thereof. In those drawings and the description below, like numeric designations refer to components of like function. Specific terms used in that description are intended to refer only to the particular structure of the embodiments selected for illustration in the drawings, and are not intended to define or limit the scope of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is schematic front view of an exemplary high tension cable barrier fence using the post and hook configuration of this disclosure.

FIG. 2 is an enlarged view of one of the posts of FIG. 1 with the three horizontal fence members being cables and depicting a location for an optional fourth cable.

FIG. 3 is a side view of one of the posts of FIG. 1 showing the relationship of the post to the roadway and the slope.

FIG. 4 is a perspective view of a single post configuration.

FIG. 5 is a front elevation view of the post of FIG. 4.

FIG. 6 is a rear elevation view of the post of FIG. 4.

FIG. 7 is an enlarged front elevation view of a portion of the post of FIG. 5 that defines the slot that receives the hook that holds a horizontal fence member.

FIG. 8 is a section view looking down through the post of FIG. 5 perpendicular to the longitudinal axis of the post.

FIG. 9 is a perspective view of an exemplary plug.

FIG. 10 is a perspective view of the hook.

FIG. 11 is a front elevation view of FIG. 10.

FIG. 12 is a side elevation view of FIG. 10.

FIG. 13 is a top plan view of FIG. 10.

FIG. 14 is a perspective view of the front surface of the post with a hook hanging from the slot prior to the installation of a horizontal fence member under the hook.

FIG. 15 is a perspective view of the interior of a post showing the engagement of the hook with the post and the locking ribs on the plug installed in the upper portion of the slot.

FIG. 16 is a perspective view looking down from the top of a post showing a plurality of cables connected to the posts, the engagement of the top hook with the post, and the inner portion of the plug installed in the upper portion of the slot.

FIG. 17 is a front perspective view depicting a post with three horizontal fence members in the form of cables connected to the post with three hooks and plugs being installed in the upper portions of the slots above the hooks.

FIG. 18 is a bottom perspective view of a cap that can be used on the upper end of a post.

Similar numbers refer to similar features throughout the specification.

DETAILED DESCRIPTION OF THE DISCLOSURE

The drawings schematically illustrate a portion of a paved (e.g., asphalt-paved) roadway 1 located next to a slope 2, having an inclination, with a supporting reserve 3 located between roadway 1 and slope 2. The barrier fence of this disclosure is indicated generally by the numeral 4 and includes a plurality of posts 5 positioned outside the roadway 1 in ground slope 2 at a distance from supporting reserve 3 of roadway surface 1. Each post 5 can be anchored directly in the ground material of slope 2 without use of pre-fabricated foundations or foundations cast on site. One or more horizontal fence members 6 which are typically metal cables are supported by posts 5 to provide a barrier for vehicles that leave the roadway. In an exemplary configuration, each cable is a 19 millimeters, 3×7 strand galvanized and pre-stretched by 35 percent. Each cable has a nominal tensile capacity of 1400 N/mm̂2. The cable specification is DSR Galvanized 320, lay—right hand regular (RHRL).

Posts 5 can be laterally spaced about 2000 millimeters with tensioning sections 7 (shown in FIG. 1) disposed at multiple locations along the barrier. In one configuration, a tensioning section is located at about every 300 meters and about 150 meters from an anchoring location. These sections include rigging screw assemblies incorporated into each horizontal fence member 6 that allows each horizontal fence member 6 to be tensioned when installed. The amount of tension in the horizontal fence members 6 change as the temperature changes so the initial tension applied to the members 6 is defined by the temperature. In the exemplary cable configuration, the cables are tensioned at 37.3 kN at −20 degrees Celsius, 34.3 kN at −10 degrees Celsius, 31.4 kN at 0 degrees Celsius, 28.4 kN at 10 degrees Celsius, 25.5 kN at 20 degrees Celsius, 22.5 kN at 30 degrees Celsius, or 19.6 kN at 40 degrees Celsius.

Posts 5 can be rammed down into the earth or positioned in pre-made holes, such that a lower portion of post 5 anchored in the ground can have a length of at about 1198 millimeters (dimension line 50 in FIGS. 2 and 3) as measured at the up-slope wall 20 of post 5. These above roadway and below ground measurements will vary in the actual installation due to variations in the slope and the surface condition of the ground. A variation of ten percent is not unusual. Posts 5 dispose under slope 2 to a depth of 1198 millimeters provides a barrier fence with sufficient post strength and fence member retention to retain a vehicle that leave the roadway and collides with the barrier under defined MASH16 standard test conditions.

Posts 5 can be made from steel in accordance with ASTM-A1011 grade 60. When a cap 40 is used on top of post 5, the following dimensions exclude the dimension of cap 40. In an exemplary configuration, the overall length of post 5 is 2256 millimeters and, when in use, about 1298 millimeters is disposed below the roadway surface with about 1198 millimeters (dimension line 50) being disposed below the surface 52 of slope 2 to provide 958 millimeters of post length above the roadway surface to support the horizontal fencing members. As shown in FIGS. 2 and 3, the inclination of slope 2 causes the location 52 where post 5 enters the earth to be about 100 millimeters (dimension line 51) below the roadway surface 1. Three horizontal fence members can be vertically spaced 185 millimeters (dimension line 53) with the lowest being about 530 millimeters (dimension line 54) above the roadway surface. In this configuration, a fourth horizontal fencing member 6 can be added 92.5 millimeters (dimension line 55) below the top one to provide an embodiment of fence 4 that fulfils a four-cable requirement. The top horizontal fence members of both of these configurations are positioned about 900 millimeters (dimension line 56) above the roadway surface.

The inclination of slope 2 determines how far from the outer edge of supporting reserve 3 post 5 can be located. When the inclination is 6H:1V (flattest), dimension 57 is unlimited; at 4H:1V, dimension 57 is 0-400 millimeters; at 3H:1V, dimension 57 is 0-300 millimeters; at 2H:1V, dimension 57 is 0-200 millimeters; and at 1H:1V, dimension 57 is 0-100 millimeters. These maintain a desirable length of each post (subject to ground variations) below the surface of slope 2 and maintain the height of the cables with respect to roadway 1.

Fence 4 includes a plurality of posts 5 that together support a plurality of horizontal fence members 6, which, in the embodiment shown in FIGS. 1 and 2, includes three parts that are preferably positioned at mutually equal vertical distances. As also depicted, a fourth member 6 can be disposed below the uppermost member 6. In the embodiment illustrated, horizontal fence members 6 can be made as steel cables, ropes or wires. In modified embodiments, horizontal fence members 6 can be in the form of, by way of example, thin belts or rods. FIGS. 1 and 2 depict an optional location for a fourth horizontal fence member below the uppermost fence member such that the fourth member is disposed between the top two members.

FIG. 17 depicts, in perspective, post 5 of the type illustrated in FIGS. 1 and 2. Post 5 is anchored in slope 2 outside the supporting reserve at a road and have three horizontal fence members 6 in the form of steel cables arranged at substantially equal distances from each other in vertical direction. FIGS. 1 and 2 depict the locations of horizontal fence members 6 with the lowest being 530 millimeters above roadway 1, the middle being 715 millimeters above roadway 1, and the highest being 900 millimeters above roadway 1. Additional horizontal fence members 6 can be used.

FIGS. 3-13 illustrate a retaining configuration for a horizontal fence member 6 wherein the flat front surface 20 of post 5 defines a slot 11 for each horizontal fence member 6 to be connected to post 5. In the exemplary configuration, post 5 defines three vertically-spaced slots 11 shaped as a reversed “figure one” shape. Each slot 11 thus has a main vertical portion with a horizontal width of about 7 millimeters (dimension line 60 in FIG. 7) and an upper portion that extends down and outwardly. Slot 11 receives two oppositely-extending ends 13 of a hook 12. Ends 13 extend 12.5 millimeters from the main body of hook 12. Ends 13 can be straight or curved but are only curved in one plane so they contact along their lengths. The body of hook 12 is disposed over a portion of horizontal fence member 6 to hold it in place in front of post 5. Horizontal fence member 6 engages front surface 20 across the width of post 5.

Hook 12 includes a main body in the form of an S-curve that has a first hook portion and a second hook portion. The second hook portion can hold hook 12 to post 5 before cables 6 are installed (shown in FIG. 14) with the first hook portion being the one that is placed over cable 6 when fence 4 is assembled. Ends 13 project at ninety degree angles from the ends of the main body of hook 12. Hook 12 is made from 304 stainless steel.

Each post 5 includes a front wall 22 that defines slots 11, flat front roadway-facing face 20, and a flat inner face. Each post 5 also includes sidewalls 24 that extend back to a depth that is longer than the width of post 5. A rear wall 26 is formed in two portions separated by an opening 28 that extends the entire length of post 5. The wall thickness of post 5 are 4 millimeters. In the exemplary configuration, the vertical portion of slot 11 has a width. The combined contact surfaces (dimension lines 62) for members 6 on either side of slot 11 combine to have a length about six to eight times the width of slot 11.

In the exemplary configuration, slot 11 has a horizontal width of 7 millimeters (dimension line 60) and the contact length is 49 millimeters (not counting the curved corners and the slot width) provided a contact length that is seven times the width of slot 11. Slot 11 has a vertical portion that is 60 millimeters with a rounded bottom. The upper portion of slot 11 extends horizontally about 18 millimeters but also downward (about 13 millimeters drop) to form the reversed figure one shape (the upper portion can extend at an angle of about 61.4 degrees from vertical (dimension line 63).

Post 5 has a depth of 83 millimeters (dimension line 64) which is over eleven times the width of slot 11 to provide substantial resistant to bending back away from roadway 1. The width of post 5 provides ample space for the ends 13 of hook 12 along the flat inner surface 23 of front wall 22. This allows ends 13 to rest against the inner surface along their entire lengths. In the prior art system, a rounded post is disclosed that only allows for point contact between the ends of the hook and the inner surface of the post. The body of hook 12 has a thickness of 6 millimeters which provides only 1 millimeters of space for lateral movement of hook 12. The body of hook 12 is round in cross section. Post 5 thus provides a strong configuration to retaining hook 12.

Plugs 30 are fit into the top portion of slots 11 after hooks 12 are connected to posts 5. Plugs 30 can be fabricated from a metal or a polymer and help keep hooks 12 seated in the desired position with respect to posts 5 when members 6 are subjected to forces such as weather or other forces that cause them to move up with respect to post 5. Plugs 30 can be made from polypropylene and can include materials or a coating to make them resistance to ultraviolet radiation degradation. Each plug 30 has at least one resilient locking rib 31 that is snap fit into slot 11 to hold plug 30 in place. The exemplary plugs 30 have a pair of spaced locking ribs 31 that each define a locking surface 32 configured to engage the inner surface of post 5 when plug 30 is installed. Each locking rib has an angled surface at its inner end to allow plug 30 to be pushed into slot 11 and snap fit into place through the deflection of locking ribs 31. Locking ribs 31 project rearwardly from a base 33. Flanges 34 are disposed on opposite ends of base 33. Flanges 34 are sized larger than slot 11 and engage front surface 20 to prevent plug 30 from being pushed entirely through slot 11. Protuberances 35 are disposed behind both flanges. Each protuberance 35 is disposed within slot 11 when plug 30 is installed such that protuberances 35 will abut the ends of slot 11 and provide abutment surfaces for plug 30. Plugs 30 substantially fill the upper portion of slot 11 as shown in FIG. 15.

FIG. 19 depicts an exemplary post cap 40 that can be optionally used at the top of post 5. Caps 40 can be made from a polymer such as a polypropylene and can include materials or a coating to make them resistance to ultraviolet radiation degradation. Cap 40 has an outer wall 41 and an inner wall 42 that are spaced apart to define a channel 43 sized to receive the top of post 5. A top wall 44 joins the upper portions of walls 41 and 42 to close cap 40. End walls 45 close the ends of walls 41 and 42 to allow opening 28 to continue through cap 40. In an optional configuration, cap 40 includes an integrated plug 50 that takes the place of plug 30 for the uppermost slot 11. Plug 50 protrudes into channel 43 and the resilience of the cap walls allows it to be forced down over the end of post 5 until it snaps into the top portion of the uppermost slot 11 to fulfill the function of plug 30 (which is then not needed for the uppermost slot 11). A portion of the inner surface of outer wall 41 opposite integrated plug 50 can define a recess to accommodate plug 50.

Fence 4 thus provides a stronger post 5 with flat surface 20 for the hook 12. This keeps the hook 12 in place longer and keeps the cable 6 in contact longer with the post 5. The shape of the post 5 gives better support for hook 12 and cable 6 than prior art post shapes that were substantially round, oval, or curved away from the slots. The existing oval shaped posts gave much less support to the cables and hooks. The large flat front surface 20 also helps the hook 12 function better when forces from contact from a vehicle make the post 5 twist and bend. Overall, the interaction between post 5, hook 12, and cable 6 makes fence 4 perform better than prior art fences. Fence 4 provides controlled release of cable 6 from post 5 helping to keep the vehicle in contact with cables 6 which are able to retain the vehicle. Crash tests show this retention feature. Fence 4 has been tested with the same pickup truck as the prior art fence described in US Patent Application Publication 2002/0014620 and fence 4, when installed in a slope, retains the truck while the prior art fence did not.

The foregoing description has been made with reference to exemplary embodiments. Modifications and alterations of those embodiments will be apparent to one who reads and understands this general description. The present disclosure should be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or equivalents thereof.

The relevant portion(s) of any specifically referenced patent and/or published patent application is/are incorporated herein by reference. 

1. A barrier fence for a roadway; the barrier fence comprising: a plurality of posts arranged in the ground along an edge of a roadway having a roadway surface; a plurality of vertically-spaced, fence members attached to the posts; each of the posts having a wall that defines a flat outer surface with the wall having the flat outer surface defining a slot associated with each of the fence members; each slot having a horizontal width; each fence member being connected to each post with a hook disposed in the slot associated with the fence member; each fence member engaging the flat outer surface of the wall on each side of the slot at a combined contact surface; and the length of each combined contact surface being six to eight times the horizontal width of the slot.
 2. The barrier fence of claim 1, wherein the wall that defines the flat outer surface also defining a flat inner surface.
 3. The barrier fence of claim 2, wherein a plurality of the hooks includes a first and second hook ends; the hook ends having lengths; each of the hook ends being disposed inside the post in engagement with the inner surface of the wall that defines the flat outer surface along the lengths of the hooks.
 4. The barrier fence of claim 3, wherein the hook ends are straight.
 5. The barrier fence of claim 4, wherein the hook is round in cross section.
 6. The barrier fence of claim 1, further comprising a plug disposed in the slot above the hook.
 7. The barrier fence of claim 6, wherein the plug includes a locking finger that engages the post.
 8. The barrier fence of claim 1, wherein the posts are positioned outside a supporting reserve of the roadway.
 9. The barrier fence of claim 1, wherein each post has a roadway-facing wall; the roadway-facing wall extends at least about 1198 millimeters into the ground.
 10. The barrier fence of claim 1, wherein there are more than two horizontal fence members.
 11. The barrier fence of claim 10, wherein an uppermost fence member is 900 millimeters above the roadway surface.
 12. The barrier fence of claim 1, wherein the horizontal members are steel cables.
 13. The barrier fence of claim 1, wherein the ground receiving the post has an inclination down away from the roadway that is larger or equal to 6H:1V.
 14. The barrier fence of claim 13, wherein the post is spaced from an outer portion of the supporting reserve by at most 400 millimeters when the inclination is 4H:1V, by at most 300 millimeters when the inclination is 3H:1V, by at least 200 millimeters when the inclination is 2H:1V, and by at most 100 millimeters when the inclination is 1H:1V.
 15. A barrier fence for a roadway; the barrier fence comprising: a plurality of posts arranged in the ground along an edge of a roadway having a roadway surface; a plurality of vertically-spaced, fence members attached to the posts; each of the posts having a roadway-facing front wall that defines a flat outer surface; the roadway-facing front wall defining a slot associated with each of the fence members; each slot having a horizontal width; one of the slots being an uppermost slot; the roadway-facing front wall also defining a flat inner surface; each fence member being connected to each post with a hook disposed in the slot associated with the fence member; a plurality of the hooks including first and second hook ends; the hook ends having lengths; each of the hook ends being disposed inside the post in engagement with the flat inner surface of the roadway-facing wall; the hook ends disposed flat against the flat inner surface such that the entire length of each hook end is in engagement with the flat inner surface; each fence member engaging the flat outer surface of the roadway-facing wall on each side of the slot at a combined contact surface; the length of each combined contact surface being six to eight times the horizontal width of the slot; and a plug disposed in the slot above the hook.
 16. The barrier fence of claim 15, wherein the roadway-facing front wall of each post extends at least about 1198 millimeters into the ground.
 17. The barrier fence of claim 16, wherein an uppermost fence member is 900 millimeters above the roadway surface.
 18. The barrier fence of claim 17, wherein each post is 2256 millimeters long.
 19. The barrier fence of claim 15, wherein a plurality of the posts carry a cap; the caps including an integrated plug disposed the uppermost slot.
 20. The barrier fence of claim 15, wherein the horizontal width of each slot is 7 millimeters and each hook having a body that has a 6 millimeters diameter cross section.
 21. A barrier fence for a roadway; the barrier fence comprising: a plurality of posts arranged in ground disposed outwardly of a supporting reserve that borders a roadway surface; the ground sloping down and away from the supporting reserve; a plurality of spaced, fence members attached to the posts; each of the posts having a front wall that defines a flat roadway-facing outer surface with the front wall having defining a slot associated with each of the fence members; each fence member being connected to each post with a hook disposed in the slot associated with the fence member; each post also having a generally rectangular cross section with a pair of sidewalls and a rear wall; and about 1198 millimeters of the front wall being disposed under the ground.
 22. The barrier fence of claim 21, wherein each slot has a horizontal width; each fence member engaging the flat outer surface of the front wall on each side of the slot at a combined contact surface; and the length of each combined contact surface being six to eight times the horizontal width of the slot.
 23. The barrier fence of claim 22, wherein the rear wall defines a continuous slot.
 24. The barrier fence of claim 21, wherein the post has a width of about 64 millimeters, a depth of about 83 millimeters; and the front wall, rear wall, and sidewalls having thicknesses of about 4 millimeters.
 25. The barrier fence of claim 21, wherein the ground receiving the post has an inclination down away from the roadway that is larger or equal to 6H:1V.
 26. The barrier fence of claim 25, wherein the post is spaced from an outer portion of the supporting reserve by at most 400 millimeters when the inclination is 4H:1V, by at most 300 millimeters when the inclination is 3H:1V, by at least 200 millimeters when the inclination is 2H:1V, and by at most 100 millimeters when the inclination is 1H:1V. 